Current standard rack configurations are measured in rack-units (RUs). For example, a blade server may have a rack unit measuring 19 inches wide and having a pitch of 1.75 inches in height. A common computer rack form-factor is 42 RU high, which is a factor in limiting the density or number of components directly mountable into a rack. Higher density component systems are desirable since they require less space per rack enclosure and ultimately less space within the building housing the enclosures. Often these buildings must include high price high maintenance false floors to accommodate the mass of cabling and the delivery of chilled air and power to the enclosures. Another factor in determining component density is the pitch of the rack unit as often limited by the space required for component heat sinks and associated cooling components (e.g., fans).
Typically, a rack configuration is specialized and configured to perform a single function, such as server node. In this case, the rack is designed to accommodate only those rack components (e.g., modules and backplanes), which are repeated throughout the rack, for the particular designed to function. In other words, the rack unit lacks flexibility to change. For example, if requirements change that demand a new functionality or if the form factor changes for the current function, a new rack must be created to implement the new or changed hardware.